Trap for fluid in a pipe section



A. G. JONES, JR 2,716,455

TRAP FOR FLUID IN A PIPE SECTION Aug. -30, 1955 2 Sheets-Sheet 1 FiledJan. 22, 1955 A/onzo 6. Jones z/r.

INVENTOR.

A TTOR/VE Y Aug. 30, 1955 Filed Jan. 22, 1953 A. G. JONES, JR

TRAP FOR FLUID IN A PIPE SECTION 2 Sheets-Sheet 2 Alonzo 6. Jones z/r:

INVENTOR.

ATTORNEY United States Patent TRAP FOR FLUID IN A PIPE SECTION Alonzo G.Jones, Jr., Clovis, N. Mex.

Application January 22, 1953, Serial No. 332,721

8 Claims. (Cl. 166-81) This invention relates to a trap or retainerdevice which is employed to trap or retain oil and other fluid drainingfrom the sections of a pipe string as the sections are unscrewed orotherwise removed from the pipe string during its withdrawal from awell.

In the drilling, formation testing and operation of wells such as oilwells, the pipe strings, such as the drilling string or testing stringand the likemust be with drawn at varying intervals to perform variousoperations, such as changing the bit, installing formation testingtools, recovering fluid enclosed in the string, and for other purposes.Such strings will ordinarily be filled with fluid, which may be oil,water, drilling mud, etc. In order to withdraw such a string from thewell, the sections of pipe forming the string must be'successivelyunscrewed as the pipe is drawn upwardly from the well. Any fluid in thesections will drain out of the sections as they are broken out of thestring and will spill out over the derrick floor and on the men engagedin removing the pipe. The spillage of such fluids is both hazardous tothe operators and is wasteful, particularly if the pipe is filled withoil or special drilling muds. Also, it is often desirable to measure theamount of fluid inside the pipe string, particularly during formationtesting, as this may be a measure of the production possibilities of thewell.

Briefly stated, a primary object of the present invention is to providea generally tubular trap or retainer device which is adapted tosealabout the pipe string above and below the joint between adjacentsections of the pipe string and which includes a valve or gate which isadapted to close the lower end of the upper pipe section more or lessautomatically as that section is released from the next lower section tothereby prevent the uncontrolled loss of fluid from the removed section.

Another object is to provide a tubular body, split longitudinally andhinged at one side so that it may be closed about the pipe string andprovided with sealing means at its opposite ends to seal about the pipeabove and below a connection between pipe sections, the body beingsupported on the upper pipe section to be moved upwardly therewith asthe upper section is withdrawn from its connection with the next lowerpipe section, the body being provided with a shutter or gate which willautomatically close the bore of the body below the lower end of theupper pipe as it is separated from said next lower section.

A further object is to provide a sealing sleeve adapted tolongitudinally span the joint between a pair of pipe sections andprovided with an automatic shutter to close between the ends of sectionsas they are separated.

Other and more specific objects and advantages will become apparent fromthe following detailed description when read in conjunction with theaccompanying drawing which illustrates a useful embodiment in accordancewith this invention.

In the drawing:

Fig. l is an elevational view of the trap device in 2,716,455 PatentedAug. 30, 1955 accordance with this invention shown in position about thejoint between connected sectionsof a generally conventionai pipe string;

Fig. 2 is a view generally similar to Fig. 1, showing the pipe sectionsafter being disconnected and showing the trap shutter in closedposition;

Fig. 3 is a cross sectional view taken generally line 3-3 of Fig. 1; and

Fig. 4 is a cross-sectional view generally similar to Fig. 3 but showingthe parts of the trap body in the open position preparatory to beingclosed about the pipe string.

In the drawing there-is shown upper and lower pipe sections 5 and 6,respectively, forming adjoining sections of a conventional string ofdrill pipe or tubing. The pipe sections, as illustrated, may be formedofconventional external upset pipe having external upset portions 7 and8, respectively, at their ends terminating in externally threaded pins 9and 10, respectively, and forming external shoulders 11 and 12,respectively, at the junctures of the upset portions with the pipe. Thepipe sections are connected together by means of a conventional screwcollar 13, having internally threaded boxes 14 and 15, respectively, atits upper and lower ends to receive the respective pins 9 and 10. 1 v

The trap .in accordance with the present invention comprises a generallytubular sleeve-like body 16 composed of two complementarysemi-cylindrical portions hinged together at one side by means of hinges17 (Figs. 3 and 4) so that the parts of the body may be swung apart toopen it'and to be then closed about the pipe string. A latch 18, of anysuitable and generally conventional form is mounted on the side of thebody opposite the hinges to lock the parts of the body in closedposition about the pipe string.

The upper end of body 16 is provided with an inwardly extending annularflange or shoulder 19, the bore; of which is preferably made somewhatsmaller in diameter than that of upset portion 7, so that it will engageshoulder 11 and prevent pipe section 5 from beingwithdrawn upwardlythrough the upper end of body 16, although pipe section 5 is free torotate relative to body16. An annular sealing ring 20, constructed ofany suitable resilient material such as rubber or rubberfabriccomposition is suitably secured to flange or shoulder 19 and is arrangedto project annularly therefrom so as to compressively engage the outersurface of pipe section 5, preferably about shoulder 11, as shown, whenthe body is closed, to thereby form a fluid-tight seal between the pipesection and the upper end of body 16.

The length of body 16 is made such that it will longitudinally span thejoint between the pipe sections when the latter are screwed together'inthe usual made-up condition, and will extend downwardly about theexterior of collar 13 some distance below the upper end thereof, as bestseen in Fig. 1. At its lower end, body 16 is provided with an inwardlyprojecting annular sealing ring 21 which is constructed of resilientmaterial and is adapted to form a fluid-tight slidable seal between thelower end of body 16 and the exterior of collar 13, when the trap isclosed about the body.

A shutter 22 of generally circular shape is connected at one side bymeans of a crank arm 22a to a longitudinally extending pivot pin 23rotatably' journaled in a bracket 24 mounted on the exterior of oneportion of body 16. This portion of the body is provided with ahorizontal slot 25 through which shutter 22 may enter the interior ofbody 18 from the exterior thereof. A coil spring 26 is mounted about pin23 between the bracket and the shutter to urge the shutter to its inwardor closed position. A pair of longitudinally spaced guide rings or alongshoulders 2727 are mounted on the interior of body 16 to guide shutter22 in its movement into the interior of body 16 and to hold it firmly inplace when in the closed position. It will be understood that thespacing between guide rings will be made such that shutter 22 will fitsnugly between them so that there will be minimum seepage of fluid pastthe shuttter from the interior of the body above the shutter. Ahorizontally disposed generally flat housing 28 is mounted on theexterior of body 16 and is shaped to enclose shutter 22 when the latteris in its open position and to permit horizontal swinging movement ofthe shutter between its open and closed position. Housing 28 is closedthroughout its periphery and its inner end is secured to the exterior ofbody 16 surrounding slot 25 by any suitable fluid-tight connection. Thishousing serves to prevent loss of fluid from body 16 through shuttterslot 25, since it encloses the slot, the shutter and the path ofmovement of the shutter to and from its bore-closing position.

A drain pipe 29 communicates with the interior of body 16 at a pointjust above shutter 22.

The above-described device is employed in the following manner:

The trap will initially be in the open position shown particularly inFig. 4 and will be mounted on the pipe string by closing the parts ofthe body about collar 13 and the adjacent portion of pipe section 5 asshown in Fig. 1. When thus closed about the pipe string, shutter 22 willoccupy the position shown in greater detail in Fig. 3 in which theshutter will be held in the open position against the urging of spring26 by its engagement with the exterior of collar 13. The upper end ofthe body will be sealed with the exterior of pipe section 5 through ring20. The lower end of the body will be sealed about collar 13 by means ofsealing ring 21.

As upper pipe section 5 is unscrewed from collar 13 it will moveupwardly. Its upward movement will engage flange or shoulder 19 drawingbody 16 upwardly with it over the surface of collar 13. At the instantpin 9 becomes completely unscrewed from the collar and moves above theupper end of the collar, the spring pressure on shutter 22 will swingthe latter to the closed position, shown particularly in Fig. 2,trapping liquid in pipe section 5 in body 16. This liquid may then bedrained ofi? through drain pipe 29 to any place of disposal desired. Thelower end of body 16 will still be engaged about the upper end of collar13 at the moment the shutter closes so that very little fluid can escapeat any stage of the separation of the pipe sections.

After the fluid has been drained off through drain pipe 29, the trap maybe opened and removed from the end of section 5 in readiness forattachment about the next joint as it is withdrawn from the well.

It will be understood that numerous alterations and changes may be madein the details of the illustrative embodiment within the scope of theappended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

l. A device for trapping fluid in a pipe section being removed from apipe string, comprising, in combination with a vertically disposed pipestring composed of pipe sections connected end-to-end by means ofthreaded joints,

a generally tubular body removably mountable on said string surroundinga joint between upper and lower adjacent pipe sections, means forsupporting said body on said upper section for movement upwardlytherewith as it is unscrewed from the lower pipe section, and ahorizontally disposed shuttter member movably mounted on said body toclose the bore thereof below said upper section as the latter iswithdrawn from said lower section.

2. In a device as defined in claim 1, resilient means urging saidshutter member to the bore-closing position.

3. In a device as defined in claim 1, annular seals between said bodyand said pipe string above and below said joint.

4. A device as defined in claim 1 wherein said body is composed of apair of complementary semi-cylindrical segments hingedly connected atone side, and releasable latch means connecting said segments at theopposite sides. I

5. In a device as defined in claim 1, a horizontally disposed housingmounted on the exterior of said body and enclosing said shutter memberand its path of movement to and from its closed position.

6. In a device as defined in claim 1, a drain pipe through the wall ofsaid body communicating with the interior thereof above said shuttermember.

7. A trap for fluid in a pipe section, comprising, a generally tubularbody removably mountable about the exterior of a pipe section to extendbelow the lower end thereof, sealing means mounted on the body to form aseal about the exterior of the pipe section above the lower end thereof,means for supporting the body on the pipe section above said lower end,a horizontal slot through the wall of said body adjacent the lower endthereof, a shutter member pivotally connected to the exterior of saidbody positioned to swing through said slot to close the bore of saidbody, resilient means urging said shutter member toward the bore-closingposition, and a horizontally disposed housing mounted on the exterior ofsaid housing enclosing said shutter member and its path of movement toand from its bore-closing position, the inner end of said housing beingsealed about said slot.

8. A trap for fluid contained in an upper pipe section being unscrewedfrom its joint with a sub-adjacent pipe section, comprising, a sleevemember surrounding the joint and extending above and below the joint,sealing means mounted on the sleeve member to form fluid-tight sealswith the exterior of the pipe sections above and below the joint, meansfor supporting said body on the upper pipe section for movement upwardlytherewith, and movable shutter means mounted on the exterior of saidsleeve member and automatically movable across the bore of the sleevebetween the ends of the pipe sections as they are separated.

References Cited in the file of this patent UNITED STATES PATENTS WalkerNov. 23, 1880

